Editing/Changing an Existing Mail Merge Spreadsheet; Importing New Data; Replace Spreadsheet

You will want to be in Step 3 Customize:

• Click in the text box that has the older data you want to replace

• Then go back to the left-hand side and select Import Data
• Select Replace Spreadsheet

• Finally, select Browse for File to import your new Spreadsheet. Follow the steps to Choose Fields then Arrange Fields to Finish.

To learn more about this, watch this video: